Influence of carbon and nitrogen sources on the transition from yeast-like cells to chlamydospores in Aureobasidium pullulans

The transition from yeast-like cells to chlamydospores of Aureobasidium pullulans can be induced by growing the microorganism on a glucose medium with a limiting nitrogen source and a low buffer capacity. When glucose is used as the carbon source, a concentration higher than 3% (w/v) is required to induce the transition. On the other hand, growth limiting concentrations of the N source (ammonium sulphate) are not required, and higher concentrations actually stimulate the appearance of chlamydospores. Other N sources, such as glutamate or ammonium phosphate, do not induce the transition from yeast-like cells to chlamydospores.